An advantage of the bar lock according to the present invention is that said cylinders are of conventional type used in normal locks, and are readily available commercially.
In this respect, bar locks are currently known which operate with a cylinder provided with a specially constructed gear wheel.
These bar locks consist essentially of two toothed plates engaging said gear wheel which when rotated causes the two plates to advance or retract, to thus close or open the door respectively. This type of bar lock has the serious drawback of operating only with a special type of cylinder which is difficult to obtain and replace if faulty.